645RFE

[Tommy Creekmore]

I have a 2013 Ram 1500 2wd, 4.7L and 645RFE. Do they make shift improver kits for this trans? Is it worth it to have one built? Everyday/ Street driving , what options are their?

 

[Lyle Longboat]

https://www.ebay.ca/itm/260118927324
This would help out your shifting.

 

[LoadedExpressRam]

Check out Sonnax products for the RFE's.

 

[Burla]

You are a little late to the party, as in you have many years current rfe, so would upgrading pay off? How many miles? And yes the weaknesses are known and addressable.

 

[Burla]

These are the weaknesses, if done early enough the valve body work can extend the life of the rfe transmission. Just watch these for info, I'm not saying one brand is better then another, but you see what is needed. IMO if you are near 100k miles or more, I'd roll with what I got, I wouldn't throw good money after bad, because tossing 2-3 g's (plate, shift kit, tune, solenoid, etc) into the VB wont get you any credit when it came time to replace rfe. I'd be looking at a new VB with upgrades, as prepping old valve body for warpage can be challenging.

A decent cheap option, throw a **** kit with gasket on it, piston rings get psi up in that vb, new fluid. Yeah, imo this is worth it. RFE VB comes off easy. Look into metal thread upgrade if you do this, the metal thread for the filter.

 

[kurek]

Yes, TransGo makes a shift kit for this transmission. If you only do the valve body part you can do it with the transmission in the truck, it's not hard just get yourself a big piece of cardboard or a big towel you can throw away afterward, and a sharpie. drop the pan, drop the valve body, use your sharpie to draw "boxes" on the cardboard or towel so you can lay out all the pieces and keep them organized. Follow the instructions swapping pieces, reinstall the valve body, throw the resistor they give you in the trash, fill back up with trans fluid and enjoy the drive.

The transgo RFE shift kit just shortens up the overlap duration on shifts and makes it feel slightly closer to how the 8HP shifts.

It was a night and day difference on my old WJ, but I didn't feel the need to install one on my Ram.

 

[Lyle Longboat]

I grabbed the updated solenoid pack, billet valve body channel
Plate, transgo shift kit, larger aftermarket cooler, larger trans deep pan, and billet Sonnax accumulator positions for my 545rfe, plus the circle D torque converter. I have a sonnax line pressure booster but don’t think I’ll be running that with the shift kit.

 

[Lyle Longboat]

Of course, thanks to @Burla for the lay out of what I should run in the RFE and that video he directed me too on another thread!

 

[Tommy Creekmore]

You are a little late to the party, as in you have many years current rfe, so would upgrading pay off? How many miles? And yes the weaknesses are known and addressable.

You are a little late to the party, as in you have many years current rfe, so would upgrading pay off? How many miles? And yes the weaknesses are known and addressable.

Truck has 204,500 miles, fluid and filter change at 130,000 miles. Ben checking color and smell of fluid. Going to change fluid here soon.

 

[Tommy Creekmore]

Yes, TransGo makes a shift kit for this transmission. If you only do the valve body part you can do it with the transmission in the truck, it's not hard just get yourself a big piece of cardboard or a big towel you can throw away afterward, and a sharpie. drop the pan, drop the valve body, use your sharpie to draw "boxes" on the cardboard or towel so you can lay out all the pieces and keep them organized. Follow the instructions swapping pieces, reinstall the valve body, throw the resistor they give you in the trash, fill back up with trans fluid and enjoy the drive.

The transgo RFE shift kit just shortens up the overlap duration on shifts and makes it feel slightly closer to how the 8HP shifts.

It was a night and day difference on my old WJ, but I didn't feel the need to install one on my Ram.

 

[Tommy Creekmore]

Thanks for the information